Date:	Fri, 17 Dec 93 19:51:37 +0100
From:	buers AT dg1 DOT chemie DOT uni-konstanz DOT de (Dieter Buerssner)
To:	BILLM AT vaxc DOT cc DOT monash DOT edu DOT au
Cc:	djgpp AT sun DOT soe DOT clarkson DOT edu
Subject:	Re: suggestion for NPX initialization

   That's me
   > result instead.  Also -- an may be more important -- then the result
   > of a calculation does not depend on the status of the NPX when the
   > program is called.

Bill writes

   I don't understand this statement. Provided that the FPU is properly
   initialized (set the cw, clear the sw, etc) then the results never
   depend upon the state of the FPU before the initialization.

I probably was wrong. I overlooked, that the `finit' instruction will reset 
the control word (correct?). The code section for initialization is

   fninit
   fnstcw temp87
   wait
   and temp87, 0xfffah
   fldcw temp87

I was suspicious because I found better results with a math test package
(paranoia), after setting the control word to 0x137f.

Dieter


  

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